How to Solve Excessive Fuel Injection Pulse Width?
3 Answers
Below are the causes and solutions for excessive fuel injection pulse width in vehicles: 1. Check the oxygen sensor and coolant temperature sensor: Inspect whether the coolant temperature sensor has aged, and replace it with a new one if it has; 2. Observe idle speed: Excessive fuel injection pulse width usually needs to be considered together with idle speed. High idle speed and large pulse width are generally caused by signal distortion from the throttle position sensor or coolant temperature sensor; 3. Oxygen sensor malfunction: If the idle speed is normal but the injection pulse width remains high, then the issue is caused by a faulty oxygen sensor.
I remember once helping a friend deal with an issue of excessively high fuel injection pulse width, which usually indicates that the fuel injection duration is too long, leading to a surge in fuel consumption and excessive emissions. Common causes include a dirty mass air flow sensor, a faulty oxygen sensor, or a vacuum line leak—all of which can cause the engine control unit (ECU) to miscalculate and increase fuel injection. During diagnosis, it's best to first use an OBD-II scanner to read the trouble codes and identify which sensor is malfunctioning. If no clear code is found, check the intake pipe for cracks or loose connections, as these can allow excess air to enter, prompting the ECU to compensate by increasing fuel injection. For repairs, start by cleaning or replacing the faulty sensor. However, if it's an ECU software issue, it's best to visit a professional shop for a software update. Regular maintenance, such as cleaning the throttle body every 20,000 kilometers, can prevent such issues. I've also noticed that some cars experience this due to excessively high fuel pressure, so checking the fuel pump and filter is also important—don't let small issues turn into big problems.
As a seasoned driver with over a decade of experience, I've encountered the issue of excessive fuel injection pulse width, which made the car feel sluggish and emit black smoke. The main causes are usually an aging oxygen sensor giving inaccurate signals or severe carbon buildup in the throttle body tricking the ECU into thinking there's insufficient air intake. My advice is to start simple: first, inspect the engine bay yourself for any leaks, such as damaged intake pipes or loose fuel injector connections. If you don't have tools, don't force it—just connect a Bluetooth OBD adapter to your phone to check real-time data. When troubleshooting, I usually try replacing the oxygen sensor first; if that doesn't work, then check the MAF sensor. After fixing it, I found that regularly keeping the air filter clean significantly reduces the risk. In short, this issue can't be delayed—it not only increases exhaust pollution but may also cause engine overheating and premature wear. Get it checked by a skilled mechanic ASAP.
